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When to Plant Radicchio in Martin County, NC

Martin County, North Carolina Zone 8a May

What to do in May

A quick May briefing for Martin County, North Carolina gardeners — what's urgent, what's next, and what can wait.

Avg. last frost March 26
Avg. first frost November 12
Soil temp (4") 68°F
Watering Low
Pest pressure Moderate
Daylight 13.9 hrs
  1. Collect radicchio at their peak

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

Looking ahead to June
  • First harvests: radicchio

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Radicchio is an Italian chicory with stunning red and white leaves and a pleasantly bitter flavor. It forms tight heads and is used in salads, grilled, or braised.

Martin County, North Carolina is in USDA Zone 8a. The average last spring frost is March 26 and the first fall frost is November 12, giving you a growing season of approximately 231 days.

At an elevation of 565 feet, Martin County receives approximately 46.9 inches of rainfall annually with predominantly clay loam soil. Summer highs average 92°F, providing good warmth for Radicchio during the growing season. Clay soil retains moisture well for Radicchio, but amend with compost to improve drainage and prevent root rot.

Martin County, NC (Zone 8a) Long season
231 days
Last Spring Frost March 26
231 growing days
First Fall Frost November 12
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Martin County Soil Profile

Soil Type

Clay Loam

Soil pH

5.5-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (133 days to spare)
Start indoors: Feb 13 Transplant: Mar 20 🍅 Harvest: May 22 – Jun 26
Recommended (50%) ✓ Fits season (133 days to spare)
Start indoors: Feb 19 Transplant: Mar 26 🍅 Harvest: May 28 – Jul 2
Safe Start (90%) ✓ Fits season (136 days to spare)
Start indoors: Mar 5 Transplant: Apr 9 🍅 Harvest: Jun 11 – Jul 16

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in Martin County

How your county's soil matches Radicchio's growing requirements.

Soil pH

Your soil pH (5.5–6.5) overlaps with Radicchio's range (6.0–7.0), though not a perfect match.

Soil Texture

The clay loam soil in Martin County is excellent for Radicchio — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.3%). Annual compost additions will help Radicchio.

How to Plant Radicchio

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Radicchio

4
successive plantings in your 231-day season

Sow every 6.9 weeks. Last sowing by Aug 24 to harvest before frost.

For a dedicated fall crop, sow by Sep 03.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Radicchio

Radicchio needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.

Month Radicchio Needs Rainfall You Supplement Action
Jan 4.1" 0" ❄️ Dormant
Feb 3.7" 0" ❄️ Dormant
Mar 3" 5" 0" ✅ Rainfall sufficient
Apr 3" 3.2" 0" ✅ Rainfall sufficient
May 3" 3.8" 0" ✅ Rainfall sufficient
Jun 3" 4.1" 0" ✅ Rainfall sufficient
Jul 3" 4.3" 0" ✅ Rainfall sufficient
Aug 3" 5.1" 0" ✅ Rainfall sufficient
Sep 3" 3.4" 0" ✅ Rainfall sufficient
Oct 3" 3.4" 0" ✅ Rainfall sufficient
Nov 3" 3.3" 0" ✅ Rainfall sufficient
Dec 3.7" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Martin County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Radicchio Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Radicchio needs ~1,330 GDD — county provides 4,389 GDD Excellent fit

Radicchio Planting Timeline — Martin County, NC

Radicchio Planting Calendar

Activity When Date Range
Start Indoors February 19 Feb 19 – Mar 5
Transplant Outdoors March 26 Mar 26 – Apr 9
Direct Sow March 12 Mar 12 – Apr 2
Harvest May 28 May 28 – Jul 2
Fall Sowing September 3 Sep 3 – Sep 17

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Start Indoors Transplant Outdoors Direct Sow
April Transplant Outdoors Direct Sow
May Harvest
June Harvest
July Harvest
August
September Fall Sowing
October
November
December
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Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.7"/week · Natural rainfall sufficient

📅 Days to Maturity

60–80 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 8a

📆 Growing Season

231 days in Martin County

Growing Tips for Radicchio in Martin County

Direct sow Radicchio outdoors after March 26 in Martin County when soil has warmed and frost danger has passed.

With Martin County's clay soil (29% clay), work in 3-4 inches of compost before planting Radicchio. Avoid tilling when soil is wet to prevent compaction.

Common pests for Radicchio in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

Start in late summer for fall harvest. The red color develops with cool nights and light frost. Harvest when heads are firm and compact.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Radicchio in Martin County, NC?

Martin County is in Zone 8a with an average last frost of March 26. Plan your Radicchio planting based on this frost date — see the calendar above for exact timing.

What planting zone is Martin County, NC?

Martin County, North Carolina is in USDA Hardiness Zone 8a. The average last spring frost is March 26 and first fall frost is November 12.

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Your Martin County Garden Planner — Free

A 24-page printable planner built for Martin County (Zone 8a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Martin County, NC. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.